07 - Logical Reasoning Math Questions with Answers and Explanation (2+1=31, 3+2=51, 4+3=71, 5+4=91, 6+5=?)

Having good practice on logical reasoning math questions is very important to crack any online written test. To solve logical reasoning math questions, you do not need to know complex math formulas. You just need to have basic math skills (Addition, Subtraction, Multiplication and Division) along with logical thinking.

However, the most important thing over here is the time that you are taking to solve the question. If you are able to solve the logical reasoning math question within a minute then you will get enough time to solve other criteria questions which may take more time. So that, you can easily crack any online written test.

How to solve logical reasoning math questions within a minute?

The answer is Practice!!! As I said above, you just need basic math skills, logical thinking skills and practice.

Practice maximum questions which are available here and improve your logical reasoning math skills.

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Logical Reasoning Math Question:

Find the number which replaces the question mark (?).

2+1 = 31

3+2 = 51

4+3 = 71

5+4 = 91

6+5 = ?

Answer With Explanation For Logical Reasoning Math Question:

Take the first equation i.e., 2+1=31.

Consider this as A+B = CD. 

Then the actual logic behind this is C = A+B, D = A-B

i.e., 2+1 = 31 [2+1 = 3][2-1 = 1]

Lets implement this on all the given equations.

2+1=31 (Actual Logic: 2+1 = 31 [2+1 = 3][2-1 = 1])

3+2=51 (Actual Logic: 3+2 = 51 [3+2 = 5][3-2 = 1])

4+3=71 (Actual Logic: 4+3 = 71 [4+3 = 7][4-3 = 1])

5+4=91 (Actual Logic: 5+4 = 91 [5+4 = 9][5-4 = 1])

6+5=?  (Actual Logic: 6+5 = 111 [6+5 =11][6-5 = 1])

So, the answer is 111.

Tip: Do not look only at the first equation (i.e., 2+1=31) and start thinking how it is equal to 31. Look at two or three equations and try to find the common thing in it. In this scenario, the common thing is [C = A+B], [D = A-B]. You may not get it, but you will definitely get it after practicing these kinds of questions regularly.

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